Grinding machine



6 Sheets-Sheet 1 Filed Dec. 29, 1924 .July 29, 1930.

J. BATH GRINDING MACHINE.

Filed Dec. 29, 1924 6 Sheets-Sheet 2 nillilili July 29, 1930. J. BATH 1,771,948

GRINDING MACHINE Filed Dec. 29, l924 6 Sheets-Sheet 3 lllllx III II Will: 4 i 4 llll I w M. A ggg e 7 July 29, 1930. v J. BATH 1,771,948

GRINDING MACHINE Filed Dec. 29, 1924"- 6 Shee ts-Sheet 4 July 29, 1930. J. BATH GRINDING MACHINE Filed Dec. 29, 1924 6 Sheets-Sheet \N MW J. BATH GRINDING MACHINE July 29, 1930.

Filed Dec. 29, 1924 6 Sheets-Sheet 6 '3 in the'drawin-gs in which:

Patented July 29, 1930 res l ears JOHN BATH, OF WORCESTER, MASSACHUSETTS eninnrne Macnnvn App1ication filed December 29, 19%. Serial No. 58,559.

; t standard and in which the work is supported upon a table which is slidable transversely with respect to said base or standard.

A grinding machine of this generaltype is shown in my prior Patent No; 1,202,018,

nissued to me October '24, 1916, and it is the general object of mypresent invention to imvbed 20 having a postor standard 21 (Figs. 4;

1 prove the construction therein shown, thus producing amachine'which is convenient to manufacture and which is effective and .1 reliable in operation 1 "With these general objects in view, import'ant features of my invention relate to the provision of an improved frame construction and arrangement; to novel devices for sup- 9 porting and driving either one or two pieces of work ;,to an improved table driving mechanism to improved arrangement of bearingsfor the wheel shaft to'an improved work table construction; tomeans for axially oscillating the wheel shaft; and to other arrange ments and combinations of parts which will be hereinafter described and more particu-v may pointed out in the appended claims.

A preferred form of the invention is'shown Fig. 1 is a plan view of my improvedgi'inding machine; I i Fig. 2 is a front elevation thereof;

8 is a right hand side elevation thereof; 7

35 Fig. 1 is a'sectional front elevatio mtahen along the line 4l-'1 in Fig. 1; g

Fig.6 is apartialplan view of the bed or, post of my improved machine, with the-post or standard shown in section, Fig. 6 is a detail transverse sectionalele vation, taken along the line 6-56in Fig. 1;

Fig. 7 is enlarged left hancl'side eleva ion, iookingin the direction of the'arrow 7 in Figsfl and f, I

8 is an enlarged shown in ,7 5 p p Fig, 9 is a longitudinal sectional elevation plan view of the parts of on of the work driving heads; I F5 10 is a deta l sectional plan v ew, taken along the line 10-10 in Flg. 9;

many of its .so desired.

ing'a modified work table construction and F i'g. 12 isa detail plan view showing the provision for dressing the grinding'wheel Referring-to the drawings, I have shown a grinding machine particularly designed for grinding cylindrical or conical work, al-

though the" machine is obviously adapted in features to many other kinds of work. M My improvedmachinecomprises a; base or and 5') rising from a rearwardly and laterally offset portion of the base; The standard 21 -n1ay be formed as aseparate member secured to the base bylbolts 22, as indicatedin' Fig.

Fig. 11 is a detail sectionalelevation, showl,-or it may be formed integrally therewith if Q The base "20is preferably provided with bearing surfaces 22, 23 and 24,;fo-r the table slide 25, as indicated in Fig. 4. The bearings 22 and 23 may be fiat plane surfaces and the bearing 2 f: is preferably V-shaped so as to guide the table slide 25"accurately alongside the post or standard 21.

A nut 26 (F ig 6) is clamped to the bed 20.

and is threaded to receive a feed screw 27 ro- :tatably mounted'in bearings in the table slide p 25. The feed screw 27 is provided with the Y usual hand wheelv 28 by which the table slide may be adjusted rearward and forwardso Y as to move .thework toward and from the Wh lW. 1 4

The grindlng wheel is mounted =ona wheelshaft or spindle 30 (F ig -,l) I rotatable' in bearings 31, 32 and 33. The bearings 31 and 32jaremounte'd-ona'slidingplate34 (Fig.3) l

which is movable axially of the wheel shaft in guide-ways iio and 36 by meansof a feed screw '37 andnut 38, as indicated in'Fig; 3;

. The guide-ways 35 and 36 extend across the face of thestandard-21 and also'across an overhanging projecting portioniQ (Fig.

4) of the standard, 21. The portiondO is arranged substantially, at. the rear of the bearing surface 24E (Fig. 5)'.of the bedr20,

It is" also spaced above t-he bed so thatthere 1s nointerference with the rearward and forward movement offthe tableslide' 25;

The outer shaft bearing 33' (Fig. 1) "is using very Wide I provide an annular groove 53 (Fig. 8) near mounted for axial adjustment, if desired, in guide-ways 41 (Fig. 7 in a frame memberl2 projecting upwardly at the left hand side or the bed 20. The wheel shaft is preferably provided with a tapered seat for the wheel 7 and may be provided with an additional tapered seat 43 for an additional wheel. The outer end of the shaft 30 is accordingly somewhat reduced in diameter, as indicated at 4A.

The wheel shaft 30 is thus very firmly and rigidly supported on the post or standard 21 and receives additional support from the bearing 33 on the frame member 42. The wheelvV is mounted on the shaft 30 closely adjacent the bearing 32 and the shaft 30 is of ample size and weight, so that the wheel runs with great steadiness and with. much reduced vibration.

The bearings 31, 32 and 33 are of special construction but are, notv claimed specifically herein, as they form the subject matter of a companion application Serial No. 1,702, filed January 10, 1925. F or the purposes of this application, it is sufiicient to state that each bearing includes a lower half-bearing member 46 (F i 7 and an upper half-bearing member 47.

The member 47 is carried in a cap 48 pivoted at 49 to a bracket 50 which is vertically adjustable toward and from the bearing member 46. An adjusting screw 51 alsopermits angular adjustment of the cap48 relatively to the bracket 50. The spindle bearings may thus be very easily and accurately adjusted and provide firm and satisfactory support fort-he spindle shaft.

For certain purposes, especially 7 when straight-face grinding wheels, it is desirable to slightly oscillate the grinding wheel and shaft axially during the I grinding operation. For this purpose the end of the shaft 30 and I mount an cecentric disc or cam 54 on the end of a trans verse shaft 55 rotatable 1n bearings on the.

axial movement of the wheeltends I to break up the-surface so that the wheel operates to substantially better advantage than when rotating continuously in a single plane.

The wheel shaft 30 may be driven in any convenient manner but I prefer to drive the same bya pulley (F ig.

the standard. 21. .A hood or casing en- 1) and belt orchain 62 '(F1g ;3) from a motor 64L mounted within closes the wheel W and supports piping 66 by which water or lubricant may be applied to the wheel and work. The shaft 30 is also protected by a cover 65 which is preferably mounted on the bearing member and e2:

tends adjacent the bearing flange of the wheel )V. The upper part of the table slide 25' (Fig. 1') is provided *ith a rim or band 67 a to retain water which flows down through an opening (58 into a tank 69 (Fig. 5) formed in the base 20, from which tank the water or lubricant is returned by a pump (not'shown) to the pipe 66.

A work table 2 0 (Fig. 2) is mounted to slide longitudinally 'on the table slide 25. The table 70 is preferably provided with a flat front bearing 71 (Fig. 3) and with a iishaped rear bearing '72 on the table slide 25. The table 70 is'also shown as recessed at 73 toprovidea flat surface 74 which may be engaged by a hook or clamp 75 secured. to a rear face of the table slide 25 and preventing lifting movement of the table 70 when the wneel Vv engages the work.

An alternative construction is shown in Fig. 11, in which the table 70 is provided with a flat front bearing surface 76 and with a longitudinal groove in its under side ad'- jacent the rear edge thereof, said roo-ve providing two inclined bearingsurfacesTT and 8. The bearing surface 78 is undercut or inclined upwardly and rearwardly. and the surfaces 76, 77 and 78 engage corresponding bearing surfaces on the table slide 25.

Therelative positions of the wheel W and. work K are indicated in Fig. 11 and it will be seen that any tendencyof the table '70 to swing forward and-upward about the hearing 76 as a pivot will be offset bythe engagement of the undercut surface 78 with the corresponding surface of the tableslide 25. In this form of the invention, the table is thus held firmly on its slide without the use of a separate hook. or clamp.

The table v7G maybe moved longitudinally on the table slide 25 inany convenient or desired manner, but I have shown herein a form of hydraulic feeding mechanism therefor This mechanism comprises a piston 80 2 having a piston rod 81slidable in a bearing or stufling bO X. 82 at the end of a cylinder 83 and connected at its outer end to a bracket 84 fiXGCl tO the under side' of the table 70." Pipes 85 and 86 connect the opposite ends of the cylinder 83 through a reversing valve 8'? to a pump 88 and a return pipe 89. The reversing valve 8'? is con trolled by a reverse lever 90 projecting upwardly into position for engagement bydogs 91 adjustably secured on the table 70. The lever 90 may also be'moved manually. The

pump'S-S' (Fig. 2), may .be' driven'through a sprocket 92 from any convenient source of power and a by-passipipeu93, a 'reli'ef pipe 9% and suitable valves 95, 96 and 97 are probill use

vided for controlling the operation of the hydraulic cylinderdrive. A rack 98 (Fig.

.2) and pinion 99 are provided for manual or foot rest 100 (Fig.1) which may be vertically adjustable in a stand 101 and which maybe secured in adjusted. position by a clamping screw 102. The stand 101 is also slidable longitudinally on the table and is secured in adjusted longitudinal position :by a clamping member or hook 103, the bear ing for the stand and the form of thehook being substantially the same as for the work driving heads to be described. Two such work bearing heads 104l-'105 are shown in the drawings and the head 104; will now be described in detail.

I A work center 106 (Fig. 9) is mounted in a sleeve 107 which is yieldingly pushed forward toward the work by a coil spring 108 acting against a cover plate 109. A key 110 and keyway 111 prevent angular movement of the sleeve 107, and a hand lever 112 (Fig. 10) is provided for withdrawing the spindle to permit change of work'. The lever 112' is pivoted in the frame of the head 10 1 and.

has a hook-like inward projection113 which extends into a recess 1141 in the sleeve 10?. By pulling the hand lever 112, the sleeve is withdrawn to release the work.

The frame of the head 10% is provided with bearing surfaces 116 and 117: (Fig. 3) and engages corresponding bearing surfaces on the table 70. p A hook-like bolt or clamp 118 cction 119 on the table 70 and holds the work head 10 ition.

firmly in desired iongitudinal posi For 120 (Fig. 9) mountedin aring or face plate 121 and having aring gear 122 secured thereto by screws 123- The plate 121 and gear 122 are rotatably mounted concentric with the sleeve 10? on the head-10a and are retained in position by a ring 124' which is positioned in recess formed between the parts 121 and 122 and which is secured to the head 104 by screws 12 1. ihe gear 122 is driven by a pinion 120 on a shaft 127 which may be rotated in any convenient manner andis shown herein as provided with a sprocket123 connected by a chain 129 (Fig. to a corresponding sprocket 130 on the armature shaft of an electric motor 131. j f

The work K is thus supported upon'two fixed or dead cent rs andl'OS'and is posr tively rotated by the driver 120 or by other suitable connections-to the driving plate 121.

gages a longitudinally extended rib or pro-.

rotating the work, I provide a driver It will be understood that the construction of the driving head iis identical with the construction of the head 10tabovedescribed. The heads 101 and 105 are independently adjustable toward the double tail center 100,

so that work of any desired length maybe driven by either head. If longer work-1s encountered, the stand 101 may be removed and the work may be supported between the centers 106 in the driving heads. In this case, 1": the work may be driven from both ends or one of the drivers may be removed so that the corresponding drivmg head "will act merely as a tail center or support; It will also be evident that work of different characteristics may be driven by the different heads and that the motor speed of either head may be adjusted independently 'ofthe other head.

It is desirable that the length of the double tail center 100 should eXceel the width of the wheel, sothat the wheelwill not engage two pieces of work at the same time. The provision of the double center and the separate, driving heads has been found to greatly in I crease the production of'my machine,'-as thev operator can stop one head and remove and replace the workIdriven thereby while the grinding wheel'is operating upon the Work driven by the second head.

In Fig. 12,]: have indicated provision r01 dressing thewheel VJ and for this purpose have provided a bracket 220'bolted to the tail center stand 101' and positioning a wheel dressing tool 221. for engagement by the wheel. This tool when thHS'POSflI-lQDMl"1113f] be usedto dress the wheel'eaohfltimethat it passes across from one piece (if work lite the otherpiece ofwork K...

In'Fig. 3, I have lndi'ateda"support at the rear of the wheel W in which support a wheel dressing tool 125 may be mounted. Actuating mechanism-for this wheel dressing device is not shown herein but forms the subject(matter of an additional copending application, Serial'llo. 1,703, filedgan ry 19 An opening is 'providedin'the rear of wheel casing or hood '65 (Fig. 3') for the eperationof the tool. 125"and plates 140 and 1 11 are provided cry-partially closing rear opening; All the'hydraulicftable operating mecha. i r compartment 5) in the base'20 of ,then'iachine and the "side of the base may be 1 sniare enclosed in a slotted as indicated at 131 3) to permi entrance of the pipe 86 therethrough.

Having thus described my invention the" numerous advantages thereofare believed to be readily apparent; Th-etableslide25 is 2 provided with large and rearwardly extended bearing surfaces which'permit'the workto be easily and accurately adjusted toward the wheel. The wheel shaft bearings are mounted upon a post or standard of very heavy and '1' tau rigid construction and this standard is so positioned and designed that the table slide extends under the overhanging portion there of, thus bringing the wheel above the table slide while at the same time locating the wheel closely. adjacent to the shaft bearings. lhe

provision of duplicate driving heads and a double tail center greatly increases the range of work and the speed and convenience of operation.

The specificconstruction of the guideways and supports for the sliding table are not claimed in this application but form the subject matter of a divisional application Serial No. 431,949, filed February 27, 1930.

Having thus described my invention and the advantages thereof, I do not wish to be lim ited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is r 1. In a grinding machine, a work table mounted for longitudinal movement, a double tail center secured to said table at an intermediate point, a pair of head centers non-rotatably mounted at the ends of said table and each yieldingly slidable toward and from said tail centers, separate work driving mechanism associated with each of said head centers, and means engaging said mechanism to yieldingly withdraw said head centers independently of said driving mechanism. V

2. A grinding machine having, in combination, a wheel, a wheel shaft, a work sup port, a base having a plurality of parallel transverse bearing surfaces for said work support, said support being slidable on said bearings for the wheel shaft, and a standard for the wheel shaft bearings rising from a rearwardly and laterally ofiset portion of said base entirely at one side of said work support bearings.

4:. A grinding machine having, in combination, a wheel and wheel shaft, a base having a plurality of parallel transverse bearing surfaces, a'work support slidableonsaid bearing surfaces toward and from the wheel, and a standard rising from said base entirely at one side and end of said bearing surfaces and supporting said wheel and wheel shaft, all of said bearing surfaces extending rearward out of alignment withsaid standard'and at the same sidethereof and extendinns s ing rearward substantially beyond the vertiport, a base having a plurality of parallel transverse bearing surfaces for said work support, said support being slidable on said bearing surfaces toward and from the wheel, bearings for said wheel shaft, and a standard for the wheel shaft bearings rising from a laterally offset portion of said base entirely at one side of said work support bearings, and one of said shaft bearings being ofiset from said standard and axially overhanging one of said work support bearing surfaces but spaced upwardly therefrom.

6. In a grinding machine, a wheel, a wheel shaft, a base, a standard offset from one corner thereof, bearings for said shaft on said standard, and an additional bearing for the remote end of said shaft, removablyvmounted on said base. I K

'2". A grinding machine having, in combination, a wheel, a wheel shaft, a base, awork support slidable on said base towards and from said wheel, a standard rising from said base and laterally offset from said work support bearings, wheel shaft bearings on said standard and a motor to drive said wheel shaft,

mounted in and enclosed by said standard. 7 V V 8. A grindlngniachine having, in combiation, a wheel, a wheel shaft, a base, a work support slidable on said base towards and from said wheeha standard rising from said base and laterally offsetfrom said work support bearings, wheel shaft bea ings on said standard and means to simultaneously adjust said wheel shaft bearings axially on said standard. v

9. A grinding machine having, in combi nation, a wheel, a wheel shaft, a base, a work support slidable on said base towards and from said wheel, a standard rising from said base and laterally 'ofiset from said work support bearings, a plurality of wheel shaft bearings on said standard, a

plate to which said bearings are secured, and

means to adjust said plate axially on said standard. 7

10. In a grinding machine, a work table, a pair of spaced work supports and work driving heads on said table, a double tail center for two pieces of work mounted on said table intermediate said heads, said work supports'and tail center providing means to sup= port said pieces of work substantially in axial alignmnha grinding'wheel common to both piecesof work, said work pieces being disposed within the range. of movement of A said grinding wheel, means to cause relative movement of said work and table, axially of said wheel, and means to drive each piece of work independently of the other.

11. in a grinding machine, a work table,

means to mount a plurality of pieces of work substantially in axial alignment, comprising a pair of spaced work supports and Work driving heads on said table, and a double tail center for two pieces of work mounted on said table intermediate said heads, a grinding Wheel common to both pieces of work, and means to cause relative movement of said work and table axially of said wheel, said Work pieces being located within the range of travel of the wheel.

12. In a grinding machine, a Work table mounted for longitudinal movement, separate means adjacent the ends of said table to support and rotate separate pieces of work, in substantially axial alignment with each other, means intermediate said end supports to support the adjacent ends of said pieces of work, and means to grind each piece in turn,

said work pieces being located within'the range of travel of the grinding means.

18. In a grinding machine, a work table mounted for longitudinal movement, means to mount a plurality of pieces of work substantially in axial alignment, comprising a double tail center for the adjacent ends of said pieces, centers to support the other ends of said work pieces, means independent of said double tail center to rotate said pieces of work, and a grinding wheel common to both pieces of work, said pieces being located within the range of travel of said grinding wheel.

14: In a grindingmachine, a work table mounted for longitudinal movement to permit grinding of two pieces ofwork in turn, means to support said pieces substantially in axial alignment comprising a double tail center for the adjacent ends of said pieces, centers to support the other ends of said work pieces, separate work driving devices for each piece of work, and means to actuate said devices, and grinding means having a range of movement inclusive of said pieces.

, 15. In a grinding machine, a work table mounted for longitudinal movement, means to support a plurality of pieces of work substantially in axial alignment, comprising a double tail center for the adjacent ends of two pieces of work, centers to support the other ends of said work pieces, manual means to withdraw either of said latter centers to admit the work, and means independent of said double tail center torotate said work pieces and grinding means having a range of movement inclusive of said pieces.

In testimony whereo'tI have hereunto affixed' my, signature. 7

JOHN BATH. 

